本次实验产率较低，我觉得原因有以下几点，第一，结晶之前苯甲酸含量未知，

本次实验产率较低，我觉得原因有以下几点，第一，结晶之前苯甲酸含量未知，会产生较大的误差，第二，在进行抽虑的时候外界温度过低会使部分结晶在漏斗上，

結果 (中文) 2:

In this experiment, yield is low, I think there are several reasons, first, prior to crystallization of benzoic acid content was unknown, the large error will be produced, in second, when the outside temperature is too low filitration can make partial crystallization on the funnel,